title: Probing ¹³C chemical shielding tensors in cryptolepine and two bromo-substituted analogs for antiplasmodial activity.
abstract: Density functional theory calculations were applied to investigate (13)C chemical shielding tensors in cryptolepine and its bromo-substituted analogs, 2-bromocryptolepine and 2,7-dibromocryptolepine. The fact that bromo-substituted cryptolepine shows higher antiplasmodial activity than cryptolepine raises the question of whether this effect can be related to the electronic properties around carbon atoms. The results show that changes to the principal components of the shielding tensors upon substitution are significant. In particular, σ                         (33) is the most affected tensor for carbons in the substituted ring, which could be related to the increased antiplasmodial activity of bromosubstituted cryptolepine. The analyses were also focused on atomic charges and dipole moment.
authors.affiliation: Department of Chemistry, Tarbiat Moallem University, Tehran, Iran. behzadihadi@yahoo.com
authors.forename: Hadi
authors.initials: H
authors.lastname: Behzadi
authors.forename: Mohamad Reza Talei Bavil
authors.initials: MR
authors.lastname: Olyai
authors.forename: David
authors.initials: D
authors.lastname: van der Spoel
mesh_terms: D000470:Alkaloids / Q000008:administration & dosage / Q000737:chemistry* / Q000627:therapeutic use; D000962:Antimalarials / Q000008:administration & dosage / Q000737:chemistry* / Q000627:therapeutic use; D001965:Bromides; D002247:Carbon Isotopes; D016054:DNA, Protozoan / Q000737:chemistry / Q000378:metabolism; D054879:Halogenation; D006801:Humans; D026121:Indole Alkaloids / Q000008:administration & dosage / Q000737:chemistry* / Q000627:therapeutic use; D007211:Indoles / Q000008:administration & dosage / Q000737:chemistry* / Q000627:therapeutic use; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D016778:Malaria, Falciparum / Q000188:drug therapy* / Q000469:parasitology; D008958:Models, Molecular; D010963:Plasmodium falciparum / Q000187:drug effects* / Q000378:metabolism; D011789:Quantum Theory; D011804:Quinolines / Q000008:administration & dosage / Q000737:chemistry* / Q000627:therapeutic use; D055672:Static Electricity; D013329:Structure-Activity Relationship
chemical_list: C435938:2,7-dibromocryptolepine; D000470:Alkaloids; D000962:Antimalarials; D001965:Bromides; D002247:Carbon Isotopes; D016054:DNA, Protozoan; D026121:Indole Alkaloids; D007211:Indoles; D011804:Quinolines; C024015:cryptolepine